PSX-B-13 Effect of Nutragen Supplementation on Incidence of Bovine Respiratory Disease, Weight Gain and Culling Rate in Feedlot Receiving Cattle

Abstract Bovine Respiratory Disease (BRD) is a major health issue in feedlot cattle negatively impacting growth performance and profitability. NutraGen (NG, Phibro Animal Health) is an immunomodulatory feed additive with demonstrated benefits in supporting the immune system in cattle during periods of stress. The aim of this study was to determine the effect of feeding NG on incidence of BRD during the receiving phase and the carryover performance during the full days on feed in a mixed population of feedlot cattle. Over 4 weeks, 5,125 head of mixed breeds and sex cattle from 4 regions in Argentina were weighed at arrival and assigned to treatment, CON (no NG, n=2,391) or NG (9 g/100 kg BW, n=2,734). Cattle were fed the treatments during the 30-d pre-conditioning phase only, and health and performance measurements recorded. Multivariant linear regression analysis was used to estimate the main effect of treatment. Cattle within treatment were further stratified by travel distance. After controlling for breed, sex, arrival body weight (BW), and pen size, NG cattle were 2.3% less likely to contract BRD (P< 0.01), 2.1% less likely to be discarded (P< 0.01), and gained 7.3 kg more BW than CON. NG had a greater impact on cattle that traveled longer distances. NG fed cattle traveling 630-880 km to the feedlot were 7.2% less likely to contract BRD (P< 0.01), 7.5% less likely to be discarded (P< 0.01) and gained 8.5 kg more BW compared with CON. NG fed cattle traveling over 880 km (n=1219) were 8.8% less likely to contract BRD (P=0.02), 8.7% less likely to be discarded (P< 0.01) and gained 17.5 kg more BW (P< 0.01) than CON cattle. These data support the use of NG supplementation during the pre-conditioning feedlot period to improve health and performance, especially for cattle transported over long distances.